Good for you, Deborah! It can be daunting to take charge of your health but it is so, so worth it. And I do think you're right that women in mid-life really face an unusual number of stresses that can otherwise deplete our energy and joy.
What I do is similar to what others have mentioned.
Exercise -- this is key. Until four years ago I had barely exercised in my life and was the opposite of sporty. Now I could not function well without regular exercise. I aim for a minimum of half an hour of activity a day, as Gaylene does. But the activity varies with the seasons and my schedule.
Like Janet, I have a Fitbit and enjoy using it to help me track my activity and sleep. (I don't use it as a food log, although it's possible to do that if you want.) On days when I am not working out, I aim to get my 10,000 steps through a walk.
3 to 5 times per week I do an actual workout of some kind -- resistance training (weights) at least twice (and usually 3 times), and some sort of cardio or interval training the other two days -- that might mean a run, biking, a swim, skating -- it depends on the season.
As texstyle says, resistance training is extremely important for women and often neglected. It makes a huge difference to bone health and energy levels and changes body composition -- so you lose FAT vs. muscle.
I also take a yoga class occasionally for active recovery.
I found it helpful to begin with an exercise program. (The one offered by the company I now work for). This got me acclimatized gradually. Now I mix things up. At the moment, I have a personal trainer and belong to a Crossfit facility where I go more occasionally. (I don't subscribe to many of Crossfit's more militant ideas. But I like the actual coach at the place I go and like the short intense workouts.)
Sleep -- I go through phases with this. It's harder to sleep well than it used to be, and I am guilty of staying up too late quite often. I aim for a regular bedtime, computer off an hour before bed, etc. But don't always follow my own rules. YLF is an addiction! Fortunately, exercise helps ensure a more restful sleep.
LIGHT: this is absolutely critical to me. In summer I have SOOOOO much more energy and pep and my mood is so much better overall. I bought one of those blue lights for winter, but so far it hasn't really had much of an effect. I may not be using it properly, or may need a bigger, stronger version. My need for light means it's crucial for me to get outside for a while every day. Even on our worst days I aim for that. Again -- work in progress. I don't always manage it. And suffer the consequences when I don't.
Time outdoors in nature: I don't even like running. The reason I do it is because I DO like being outdoors. Connected with above, but not identical. Time in nature -- walks or hikes. Super relaxing for me.
Diet: I'm a "moderator," meaning I don't like the idea of restricting myself or ruling out any food that I love. I refuse to count calories -- it makes me feel rebellious and unhappy. I don't follow any particular dietary philosophy. As it happens, I seem to feel and perform best on a sort of modified Paleo approach. Unlike strict Paleo adherents, I do eat dairy, legumes, and even grains . But processed grains don't really feature very often in my diet (except on holidays), I don't consume a lot of added sugars, and I focus much more heavily on vegetables, healthy fats, and lean protein. I need lean protein and a lot of it -- it helps with feeling full and it keeps my energy levels higher. So I do eat meat. But we also eat vegan and vegetarian meals several times a week -- it's just a bit more planning in the kitchen to ensure the protein needs are met. Not impossible. I watch portion sizes but do eat desserts once or twice a week, eat a square or two of dark chocolate every day, and I drink wine quite regularly.
I guess what I am saying is that food is one of my big pleasures in life, and controlling it too strictly would rob me of joy. So I wanted to find a way to truly nourish myself.
Creative work: More and more I realize that if I am not engaged in my creative work (not the paid job) I truly suffer in well being; my spiritual life withers. So I am doing my best to find ways of building more time for that again. It is a bit of a struggle with my other commitments. This is part of the phase I am in. YLF is a creative outlet in itself and very helpful and uplifting. But it is not enough for me, personally.
Community: Speaking of YLF.... But also friends. It's so important to know we are making a difference somewhere. I am sure you get this feeling in your community so maybe you don't even think about how important a part of well-being it is. But sometimes we do lose sight of it. I like the sense that I am part of a group people that shares my values and to whom I can offer something. Both here, and in real life, I try to build and be part of those communities.
Special time with loved ones: Life gets so crazy some times that I miss special time with my daughter and Mr. Suz. It really, really makes a difference when I ensure we are not robbed of that time. Going out for a nice dinner or a walk (with either or both of them), taking a short holiday...anything to reinforce that connection.
Those are my "secrets" for what they are worth! Not very original.